150/150 offenses
Just think about it. This thing has 150/150 offenses – the same as Deoxys-N, which a few of you may recall was hilariously legal in OU for a few days. The difference here is that Deoxys had the coverage and speed to handle its checks, whereas Aegislash simply can just click Shadow Ball and demolish 90% of the meta. With just one move. If you don’t resist it and don’t have invested HP/SpD approaching Heatran’s, you will be taking over half from this move alone. This isn’t even considering the fact that Aegis’ coverage is nothing to scoff at. When looking at the (hilariously outdated) moveset statistics from January, Mandibuzz, Gliscor and Bisharp were the three most common Aegis switch-ins, who are all demolished by a viable move Aegis can run – Head Smash, which is sometimes seen on Life Orb sets KOs Mandibuzz after rocks with only paltry investment, and is severely dented with Flash Cannon. Gliscor is obviously slammed hard by Shadow Ball, and Bisharp has to be very careful switching in or it dies to a Sacred Sword. Of course, it’s unlikely that Aegis is running all of these different moves on one set, but it’s the fact that Aegis can tailor its set to beat certain counters with almost no drawbacks – very similar to Genesect – that is the problem.
On top of the fact that Aegis can nuke most of its checks with the correct move, it also is in possession of a very powerful priority move in Shadow Sneak, which, coming off even slightly invested base 150, can KO a lot of switchins to Aegis after they’ve taken a Shadow Ball.
252+ SpA Spooky Plate Aegislash-Blade Shadow Ball vs. 0 HP / 4 SpD Keldeo: 208-246 (64.3 - 76.1%)
24 Atk Spooky Plate Aegislash-Blade Shadow Sneak vs. 0 HP / 0 Def Keldeo: 82-97 (25.3 - 30%)
Even with minimum rolls on both, you do at least 90%, which KOs after two turns of rocks, one LO tick, or just about any residual damage you can think of. This is an INSANE amount of damage to something with respectable 91/90/90 defenses, and shows that there is basically no sweeper in the game that can switch in on Aegis safely.
Due to a large number of factors, Aegislash can also tailor its item to suit the needs of your team effortlessly. Balanced or Offensive teams can employ Spooky Plate or Life Orb sets to smash through other offensive teams and do quite a number on more defensively oriented ones. Leftovers is also an extremely viable option, as Aegilash can create free turns for itself on virtually the entire tier by clicking King’s Shield, and forces mindgames with every sweeper that intends to set up on it. Weakness Policy, especially paired with Autotomize, turns Aegislash from the best tank in the history of the game into one that can absolute crush teams without a dedicated counter to its specific set – which makes late-game cleaning an absolute breeze. Balloon and Colbur Berry further illustrate the point that Aegislash can tailor its item to suit the needs of the team, with the former allowing you to come in for free against the likes of Garchomp, Toxic-stall Gliscor, Hippodown, etc and the latter luring in and disposing of unsuspecting Bisharp.
150/150 defenses and a protecting move that gives -2 to contact moves
252+ Atk Landorus-T Earthquake vs. 252 HP / 0 Def Aegislash-Shield: 272-324 (83.9 - 100%) -- 6.3% chance to OHKO
Yeah, that’s Adamant coming off of base 145, STAB. Essentially the most powerful unboosted Earthquake you’re likely to see in OU, and with it, you don’t even OHKO. The same can be said about non-mega Garchomp, Excadril, Gliscor (lol), Hippodown, etc etc (most of the above downright losing to Aegislash 1v1 with some combination of Shadow Ball + Sneak). Even a fully invested Life Orb Bisharp Knock Off isn’t a guaranteed kill – Aegislash is THAT bulky. So bulky in fact, that it shrugs off hit after hit from uninvested or not-super-effective foes, and responds by nuking another member of your team.
One thing that separates Aegislash from other Pokemon is the fact that not only can it not be trapped by conventional means – Shadow Tag/Magnet Pull/Arena Trap (not that any of the users in the tier can beat Aegislash 1v1 anyway), but revenge killing it in general is next to impossible. If you’re not running a Bisharp on your team or similar, the Aegislash user can simply switch out, or switch back into defense form, fucking over many of the tier’s premiere revenge killers – Banded Talonflame, Scarf users like Landorus-T, etc
EXTREMELY centralizing
Aegislash is ungodly hard on teambuilding. To build a decent team in a meta where Aegislash exists, you’re essentially forced to either run:
A.) One or more dedicated “counters” such as Mandibuzz, SpD Hippdown, AV Conkeldurr, Bisharp, Heatran, Umbreon – which, by the way, all lose to one or more of the sets listed above OR
B.) Several assorted checks to Aegis that either cannot switch in but can force it out (Garchomp, Keldeo, Greninja, basically every “frail” sweeper in the tier that can hit it super effectively)/cannot force it out but can take multiple hits from it (Vaporeon, Ferrothorn, non-Heat Wave Zapdos, etc)
And usually there’s a bit of both. Sweepers like Latios become a liability on most teams, as a free switch into Aegislash means another member of your team is about to take over half from a counter attack. Not even beginning to mention ‘Mons like Gengar and Alakazam who are OHKO’d from full by a Shadow Sneak (or Pursuit, which is a move Aegis can easily run on Lando/Keld/Pursuit trap and similar cores).
Creates 50/50 mindgame situations constantly – aka why Aegis cannot be set up on
Most things that would love to set up on Aegis are forced to either do so and take 65%+ from Spooky Plate Shadow Ball, or attack and are denied setup. Even leads like Heatran or Landorus-T, who were and are Stealth Rock using staples of most teams are locked in a coinflip against an Aegislash; either get your hazard and be crippled for the rest of the match (especially harmful to leads like the above, since they have no form of recovery) or attack the Aegis and hope you didn’t just waste a turn while it used King’s Shield. The bottom line is that having a “free turn” when an Aegislash is on the opposing field is borderline impossible.
Is an unhealthily easy way to scout choice items - aka Aegis cannot be forced out by choice users
Choice users are a very rare sight in the current meta – and for good reason: how easily they’re scouted by Aegislash. Previously top-tier Scarfers like Lando-T, Genesect (while it was still around), Garchomp, Keldeo, Terrakion are all stopped cold by Aegislash. You cannot overpredict while it is on the field, because it uses King’s Shield turn 1. Then, if you over-predicted and used a move like a Terrakion Stone Edge, you’ve automatically lost the exchange because you’re forced out or killed. And even if you chose the correct move in dispatching Aegislash, you are forced into yet another 50-50 situation: do they switch out into a Mon that can handle your attack? or do they stay in and deck another member of your team while you predict their switch and switch yourself? An all-around unhealthy situation completely in the Aegislash user’s favor simply because they’re using an Aegislash.
TL;DR – Aegislash is an unhealthy part of the metagame because it nukes every sweeper in the tier, can take enormously powerful hits from every unboosted ‘Mon, completely shits on stall and offense archetypes alike, forces 50/50 mindgames on all set-up mons, destroys the viability of choice users (especially scarfers) and creates huge amounts of free turns for your team simply by existing.
